DRIFTS Study of Platinum Aluminophosphate Oxynitride Catalysts

摘要

Diffuse reflectance infrared spectroscopy (DRIFTS) has been used to compare the surface structure and stability of fresh and reduced Pt-A1PON catalysts with that of A1PON support. DRIFTS reveals that surface PNH2 species participate in the anchoring process of the platinum precursor; meanwhile, the metal-phase reduction process produces a deep decrease in the specific surface and total nitrogen content of the solid. On the other hand, the three solids undergo hydrolysis in the presence of gaseous water at concentration as low as 3 ppm. As a result of this hydrolysis reaction, part of the nitride ions are transformed into easily removable PNH↑(4+) and NH surface species.